c. When disconnecting wiring, always tag wires to
5-2. Failures and malfunctions may often be traced
5-5. ELECTRICAL SCHEMATIC
to relatively simple causes. Before troubleshooting a
malfunctioning tester, check for available electric
5-6. Figure 5-1 is an electrical schematic of the
p o w e r supply, loose broken or frayed wires or
tester. The numbers on the schematic refer to the
broken or slipping drive belt.
figure and index number in the Parts List (Section 7)
for the appropriate component.
5-3. TROUBLESHOOTING PRECAUTIONS
5-7. TROUBLE ANALYSIS CHECK CHART
5-4. When troubleshooting this or any electrical
equipment, observe the following precautions;
5-8. Table 5-1 is a trouble analysis check chart for
the distributor tester. The chart contains the most
a. Always use a meter range higher than the larg-
common troubles that may be encountered, prob-
est expected voltage when making voltage readings.
able cause of the trouble, and action that may be
b. Connect meter leads with the tester turned off.
taken to correct the condition. Refer to the parts list
Turn on tester to read meter, then turn tester off to
for parts replacement.
disconnect meter leads.
Electrical power switched off or disconnected.
Connect or switch on power.
Tester will not start
Drive belt broken.
Worn or defective drive belt.
Output rpm low
Repair distributor and retest.
Speed adjust does not
Overload due to defective distributor being
Damaged speed adjust mechanism.
Defective vacuum gauge.
Vacuum system does not work
Defective vacuum pump.
Defective test lead or clip.
Dwell meter does not work
Defective circuit board.
Select STD DIST or PULSE GEN as
Selector switch in the wrong position for
Stroboscope does not work
the type of distributor being tested.
Repair or connect as required.
Defective or unconnected test lead.
Defective strobe lamp.